Telephone apparatus.



0.1".BRADBURN." TELEPHONE APPARATUS. APPLICATION FILED AUG. 10, 1907.

Patented May 1 0, 1910.

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ANDREW u G. P. BEADBURN.

TELEPHONE APPARATUS.

APPLICATION FILED A-UG.10, 1901.

95?,489 Patented May 10, 1910.

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TELEPHONE APPARATUS.

Specification of Letters Patent.

Patented May 10, 1916.

Application filed August 10, 1907. Serial No. 387,949.

To all whom it may concern:

Be it known that I, CHARLES FRANKLIN BRADBURN, of the village of Delmer, in the county of Oxford and Province of Ontario, Canada, have invented certain new and useful Improvements in Telephone Apparatus; and I hereby declare that the following is a full, clear, and exact description of the same.

This invention relates to a telephone system comprising a series of telephone stations, each of which is provided with a select-ing instrument forming part of the telephone system, each selecting instrument comprising a primary mechanism and a secondary mechanism with a selecting circuit normally without current closed through the primary and secondary mechanisms of all the telephone stations to connect them in series, and an individual selecting battery for each selecting instrument arranged to be cut into the selecting circuit by the operation of the primary mechanism of its respective selecting instrument.

The invention also relates to a main telephone circuit connecting all the telephone stations in series and normally closed through the primary and secondary mechanisms of the selecting instrument of each telephone station, and a normally open local telephone circuit connecting each telephone instrument with its respective selecting instrument.

The invention also relates to an emergency circuit for each telephone station forming part of the main telephone circuit and arranged to be closed through the signal circuit, but incapable of being closed through the receiver and transmitter circuit, of its respective instrument whereby the signal generator current of a disturbing instru ment, can be employed to create a disturbance on the main telephone circuit, without rendering it possible for the disturbing instrument to overhear or join in the conversation, of the connected instruments.

For a full understanding of the invention reference is to be had to the following description and to the accompanying drawings in which Figure 1, represents a diagrammatic view showing three instruments connected in series. Fig. 2, is a conventional view of the primary and secondary dials and a local telephone circuit. Fig. 3, is a detail view of the operating mechanism for the secondary dial.

Figs. 4: and 5 are detail views showing the different positions of the emergency switch.

Like characters of reference refer to like parts throughout the specification and drawings.

Each selecting instrument consists of a primary mechanism, and a secondary mechanism. The primary mechanism is provided with a primary dial a, having a central stud a on which is revolubly mounted the hub of the primary pointer b. On the primary dial a are a series of indicating points numbered respectively from 0 to 40, but the number of indicating points must be at least equal to the number of instruments in series in the circuit. 011 the primary dial concentric with the center thereof is a conductor f, preferably of an annular shape having a series of projecting contact points 9, radially alined with the center of the pri' mary dial and the numbered indicating points thereon.

Concentric with the conductor f, and located between the conductor and the center of the primary dial is a broken contact ring 6, with the broken part of the ring radially alined with the Zero point 0, and the center of the dial. Contained between the ends of the broken contact ring 6 and electrically disconnected therefrom, is a contact plate 0 to which is electrically connected the main relay conductor (Z. On the annular conductor f and alined with the contact plate 0, and zero point, is an are shaped contact plate h, of a greater are than the contact plate 0. When the pointer b of the primary dial is at zero, it establishes an electrical connection between the contact plates 0 and h, for the incoming current to the local relay conductor 0 electrically connected with the contact plate h, and with the binding post j of the relay is, so that the current can circuit from the main relay conductor (Z by means of the contact plate 0, and primary pointer b to the contact plate 71-, and local relay conductor 0 to the relay 7c, and through the coils of the relay to the binding post Z, to which is connected the main relay conductor d, leading to the next instrument.

Connected to the main relay conductor d, and to the contact ring 79, are the conductors cl of the relay actuating battery 6. Owing to the absence of an electrical connection between the contact ring Z), and the contact plate a, the battery 6 is normally in an open circuit, while the primary pointer is at zero, but while the primary pointer is at zero, a closed circuit is maintained from the main relay conductor (Z, to the relay 7: so that all incoming currents on the relay conductor (Z can circuit to therelay and actuate it to close the local battery 6 through the electromagnet f, and cause the movement of the secondary pointer 9. hen the primary pointer Z) is moved from zero, it breaks the circuit from the contact plate 0 to the contact plate 71,, and engages the contact ring I) with which it remains in contact until it completes the circle of its revolution on the primary dial from 1 to 40. The contact plate 71, and the contact points 9, of the conductor f, are successively engaged by the primary pointer as it moves on the primary dial, but there is no connection between the primary pointer and conductor f other than through the contact points. Then the primary pointer is moved from the contact plate It the circuit of the incoming currents on the main relay conductor (Z is interrupted, and the circuit of the current from the positive pole of the battery 6, is closed through the contact ring 6, and primary pointer b to the contact point 9 and conductor f, to the local relay conductor 0 and relay is, as the primary pointer successively engages the contact points g during its revolution. As the primary pointer Z) moves from the contact plate in, to the first contact point g, and thereafter as it successively engages the remaining contact points g, the circuit of the battery 6, is alternately broken and closed through the relay is to provide for the actuation of the armature of the relay is. lVhen the primary pointer engages the contact point g, radially alined with the center of the primary dial and the first indicating number thereon, a circuit is closed from the positive pole of the battery e to the relay is, so that the current from the battery 6, will energize the relay and attract the armature h, and then pass from the relay 7c, of the operated selecting instrument, to that of the next selecting instrument; and so on through all the selecting instruments connected in series until it returns again to the negative pole of the battery 6, of the operated selecting instrument. When the primary pointer passes from the first contact point 9, the circuit of the current from the battery 6, is opened to deenergize the relay and permit of the armature of the relay k, resuming its normal position. lVhen the primary pointer engages the second contact point 9, the circuit for the current from the battery 6, is again established to the relay is, the continued movement of the pointer alternately closing and opening this circuit so that the armature it will be attracted and released as the primary pointer engages each contact point and passes from it. The action of the relays of all the selecting instruments in the series, is co-incident with the action of the relay of the operated selecting instrument.

The armature h oscillates in the armature frame 2", and connected to the armature frame 2" and insulated therefrom is a binding post j for the conductor Z of the local battery 6, and electrically connected with the armature i2, is the binding post for the other conductor m of the local battery 6. The binding post j is positioned in the armature frame 2" to be engaged by the armature h when attracted by the magnet of the relay is to close the circuit of the local battery 6 through the electromagnet f. One section of the battery conductor Z is connected with the binding post 0 and the other section of the battery conductor Z is connected with the other binding post p of the electromagnet f". When the armature h is attracted to the magnet of the relay 7a, a circuit for the local battery current will be closed from the local battery 6 to the binding post 0 through the electromagnet f to the binding post p and from the binding post p by means of the other section of the battery conductor Z to the binding post j, armature h, and binding post is, to the bat tery 6. When the electromagnet f is energized it attracts the armature g, and when deenergized it allows the armature g to return to its normal position. The armature 9 forms one arm of a bell crank lever 7 The lever r is fulcrumed between the points of the pivot screws 8, and each attraction of the armature 9 causes the lever r to oscillate and move the arm 5 into engagement with one of the ratchet teeth 14 formed on the hub 22 of the secondary pointer g. Each engagement of the arm 6 with a ratchet tooth 24 moves or revolves the hub '11 a distance equal to the motion of the arm t which is preferably the distance of one of the ratchet teeth, and each movement of the hub 11 causes a corresponding movement of the secondary pointer. The distance of the movement of the secondary pointer corresponds with the distance between each adjacent pair of contact points g, so that the movement of the secondary pointers of all the instruments will correspond in time and distance with the movement of the operated primary pointer.

The number of ratchet teeth on the hubs of the secondary pointers corresponds with the number of subdivisions of the primary dials so that one complete revolution of the primary pointer of the selecting instrument will cause a complete revolution of all the secondary-pointers of the instruments in series. Each secondary pointer g revolves on a stud w projecting centrally from the secondary dial w, and concentric with the stud w is a broken contact ring y. The spaces between the ends of the broken contact rings y are differently located in the various instruments and each space is positioned to correspond with its respective calling number. As shown in Fig. 2-, this space is radially alined with the center of the hub, and the number 3, and contained in the space between the ends of the broken contact rin is a contact plate 2 electrically disconnected from the contact ring y. When the second ary pointer engages the contact plate a a signal circuit is established through its respective telephone instrument as hereinafter stated.

Connected with the binding post a of the telephone instrumentis a conductor Z5 leading to the contact plate 2, and connected with the binding post 0 of the telephone instrument is a conductor t leading to the contact ring y. Connected with the binding post a is a conductor 6 leading to the contact plate 7". Normally engaging an insulated finger g, carried by the hub of the primary pointer is a spring switch it, engaged by the insulated finger 9, when the primary pointer is at Zero and which as the primary pointer moves from zero, springs into engagement with the contact plate 7. Connected with the spring switch h is the main telephone conductor 2' connected with the conductor 4) of the preceding instrument of the series. When the primary pointer has moved from zero, the finger g releases the spring switch h which immediately moves into engagement with the contact plate f. The telephone instrument is then connected by means of the conductor 0, contact plate f", spring switch It, and conductor 2' with the conductor '2). Connected to the spring switch it and to a brush is engaging the hub of the primary pointer, is a conductor Z. Engaging the primary pointer when at Zero, is a contact plate m and connected with the contact plate 721/ and with a binding post 0 of the emergency switch 2) is a conductor g. Connected to the other binding post r of the emergency switch 22 and to a brush S engaging the hub of the secondary pointer is a conductor 6''. Connected with the contact ring y is the telephone conductor o. When the primary pointer of one selecting instrument has been positioned to bring the secondary pointer of another selecting instrument into engagement with the contact plate 2, the first and second mentioned selecting instruments are connected and the signal generator to" of the first mentioned selecting instrument can be operated to transmit a current by the signal conductor a, telephone book 0, and conductor 0 to the binding part c and from there to the contact ring 12 by means of the conductor cl. From the contact ring the current circuits by the telephone conductor 1) to the telephone conductors i of the intermediate instruments, and from the conductors z'" of the intermediate instruments by means of the conductors Z and brushes s and primary pointers of the intermediate instruments to the contact plates m. From the contact plates m it circuits by the conductors and emergency switches to the conductors t and brushes 5 and secondary pointers. The secondary pointers of the intermediate instruments will not be in engagement with their respective contact plates .2 but will be in engagement with their contact rings 3 The current will then circuit by the secondary pointers to the contact rings 3 and conductors o to the conductor 2' of the second mentioned selecting instrument.

From the conductor 2'" of the second mentioned selecting instrument it passes to the switch it and then by means of the conductor Z and brush is to the hub of the primary pointer along which it circuits to the contact point m". From the contact point m it circuits by means of the conductor g to the binding post 0 and the emergency switch 3). The emergency switch is normally closed and the current circuits by the conductor 25 to the brush a and hub of the secondary pointer ot' the second mentioned selecting instrument, and from the secondary pointer the current circuits to the contact plate a and from the contact plate 2 it circuits by the conductor Z) to the binding post a and by the usual signal conductors 0 c, c, and 0 of the telephone instrument connected with the second men tioned selecting instrument to the conductor c passing to the contact ring 12 and out on the conductor 1) to the conductor 2' ot the first mentioned selecting instrument. From the conductor 2' of the first men' tioned selecting instrument the signal current passes by the switch spring lb to the conductor 6 binding post a and conductor a, to the ringing generator to of the telephone connected with the first mentioned selecting instrument.

hen the receivers m are removed from the telephone hooks c, the local signal circuits consisting of the conductors c 0 c, and 0 are opened between the binding posts a and c and the circuits through the telephone receivers m are closed by the telephone llOOl-IS engaging the contact points of the receiver conductors c. The receiver circuits through the telephone instruments are then from the bindingposts a, receiver conductors 00 receivers 00, receiver conductors 0*, telephone hooks a, and conductors 0 to the binding posts 0. With the exception of the change of the signal and speaking circuits in the local telephone cir cuits between the binding posts a and c" the circuit of the receiver and signal currents follows the same course as previously described between the connected selecting instruments.

It has been previously stated how the one selecting instrument closes the local circuit through another selecting instrument; say N o. 3, by moving the primary pointer on the primary dial to the indicating point representing the second mentioned selecting in strument, creating the necessary impulses of the electromagnet f, to operate the bell crank armature and cause the advancement of the secondary pointer g to the required position on the secondary dial.

If an intermediate telephone desires to communicate with instrument N o. 3, and fails to notice on his own dial that the in struments are in use, he can by moving his primary pointer create an additional impulse or impulses of the electromagnet of his instrument and advance the secondary pointer of all the instruments and cause the secondary pointer of instrument No. 3 to move from its contact plate a. By doing so he breaks the communicating circuits between instruments 1, and 3, but fails to establish a communicating circuit between his own instrument and .either of the other instruments. The telephone system is then disarranged, but this disarrangement can be rectified by actuating one of the primary pointers to bring the secondary pointers to Zero, and then opening the circuit breaker c", to open the main telephone circuit, so that the primary pointers can then be restored to zero without causing the movement of the secondary pointers from zero. Should two instruments; viz. Nos. 1 and 3, be connected and a third instrument; viz. No. 2, desire to use the line, a disturbance on the line can be created by the third instrument by moving his emergency switch, but without placing the third instrument in communication with either of the connected instruments.

The emergency switch 29 consists of two blades 72 79 The blade p normally closes the circuit between the conductors q, t, and the blade p normally closes the circuit from the binding post a" through the telephone receiver m. Electrically connected with the conductor 9 is a contact plate 79. WVhen the emergency switch is moved from normal, the blade p closes the circuit from the binding post a through the contact plate 79*, to the conductor and at the same time opens the circuit from the binding post a through the receiver 03, and the circuit is opened at the same time from the conductor g to the conductor 6, by the movement of the blade 32 The current from the signal generator 10 can then pass by means of the conductor 0 to the binding post a, switch blade p and contact plate 9 to the conductor 9, contact plate m primary pointer, brush k, conductor Z, to

the main telephone conductor 2' passing from the conductor 2' of the interrupting instrument to the conductor '0 of selecting instrument No. 1. The current then passes from the conductor 4) to the contact ring y and conductor cl to the binding post 0. From the binding post 0 it passes by means of the conductor 0 to the telephone hook c, and then to the receiver conductor 0*, through the receiver 00 to the conductor :0 and binding post a.

From the binding post a the current circuits by the conductor 6 to the contact plate f, and from the contact plate 7, it passes to the switch 71, which is then in engagement with the contact plate f" owing to the fact that the primary pointer has been moved from zero. From the switch it the current passes by the conductor 71 to the conductor 12 of selecting instrument No. 3, and from the conductor 0) it passes to the contact ring 3 to the conductor d and binding post a. From the binding post 0 it passes by the conductor 0 to the telephone hook c, and receiver conductor 0 through the receiver :0 to the binding post a and from the binding post 0; it passes by means of the conductor 6 to the contact plate 2, from which it then passes to the secondary pointer and brush a in contact with the hub thereof. The current circuits from the brush 8 to the conductor t and emergency switch p to the conductor g, and along the conductor 9 to the contact plate 777/ and pointer of the primary dial, to the brush 7c, and conductor Z to the main telephone conductor 2' of selecting instrument No. 3 from which it passes to the conductor 12 of the interrupting instrument passing from the conductor 2) to the contact ring y and conductor cl to the binding post 0 of the interrupting instrument. From the binding post 0 of the interrupting instrument it passes by the conductor 0 to the telephone hook c, which is in engagement with the signal conductor 0 leading through the signal set 0 to the signal generator 20'.

The operation of the signal set 0 creates a disturbance on the line and intimates to the users that other instruments are desirous of using the line. The operation of the emergency switch to open the circuit through the receiver of the interrupting instrument prevents the interrupting instrument overhearing the conversation between the other instruments.

The conductor 22 of the first instrument is connected with the conductor 2' of the second, and so on through each instrument of the series, the conductor a of the last instrument being connected with. the conductor 2' of the first one so that a main telephone circuit can be established through all the telephone sets of the instruments.

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Having thus fully described my invention what I claim as new and desire to secure by Letters Patent is 1. A telephone system comprising a number of telephone instruments, a selecting instrument for each telephone instrument, a normally open local telephone circuit connecting each telephone instrument with its respective selecting instrument, a selecting circuit connecting the selecting instruments in series, a main telephone circuit connected through all the selecting instruments, and arranged to be closed by the selecting circuit through the local telephone circuits of any selected, two, telephone instruments, and an emergency circuit forming part of the main telephone circuit arranged to be closed through the signal set of the local telephone circuit.

2. A telephone system comprising a number of telephone instruments, a selecting instrument for each telephone instrument, a normally open local telephone circuit con necting each telephone instrument with its respective selecting instrument, a selecting circuit connecting the selecting instruments in series, a main telephone circuit connected through all the selecting instruments and arranged to be closed by the selecting circuit through the local telephone circuits of any selected, two, telephone instruments, an emergency circuit forming part of the main telephone circuit arranged to be closed through the signal set of the local telephone circuit of any selected instrument, and to be permanently cut out of circuit with the receiver and transmitter of the local telephone circuit.

3. A telephone system comprising a number of selecting instruments, each consisting of a primary mechanism and a secondary mechanism, a selecting circuit passing through the primary mechanisms to the secondary mechanisms, connecting them in series, and by which the secondary mech anisms of the selecting instruments can be operated without disturbing the primary mechanisms of such instruments, a selecting battery for each selecting instrument cut into a selecting circuit by the operation of its respective primary mechanism to actuate the secondary mechanism of its respective selecting instrument and the secondary mechanisms of all the other instruments in series, a telephone instrument, for each selecting instrument, and a local telephone circuit connected with the primary and secondary mechanisms of the selecting instrument, and a main telephone circuit closed through the local telephone circuit of any selected, two, telephone instruments.

4. In a telephone system, a selecting instrument comprising a primary dial, a primary pointer revolubly connected to the primary dial, a broken contact ring for the primary dial engaged by the primary pointer during its revolution, a contact plate inter posed between the ends of the broken contact ring and electrically disconnected therefrom, engaged by the primary pointer when in its initial position, a selecting circuit conductor connected with the contact plate, a battery connected with the selecting circuit conductor and with the broken contact ring, a second contact ring concentric with the first mentioned one, a series of projecting contact plates for the second contact ring, successively engaged by the primary pointer during its revolution, a contact plate for the second contact ring, alined with the first mentioned contact plate, a secondary dial, a relay, a selecting circuit conductor connected with the last mentioned contact plate, and with the relay, an electromagnet, a battery closed through the electromagnet by the energy of the relay, a secondary pointer for the secondary dial, means actuated by the electromagnet to position the secondary pointer on the secondary dial, a broken contact ring for the secondary dial engaged by the secondary pointer, a contact plate located between the ends of the broken contact ring of the secondary dial and electrically disconnected therefrom, a telephone instrument, local telephone circuit conductors for the telephone instrument one of which is connected with the last mentioned contact plate and the other of which is con nected with the last mentioned broken contact ring, a third local telephone circuit conductor connected with the first mentioned one, a contact plate on the primary dial for the last mentioned conductor, a main telephone circuit conductor, a switch for the main telephone circuit conductor opened by, but insulated from, the primary pointer and arranged to move into engagement with the last mentioned contact plate when the primary pointer has been moved from its initial position on the primary dial, a conductor leading from the main telephone circuit conductor to the primary pointer, an emergency switch for the telephone instrument, a contact plate on the primary dial engaged by the primary pointer when in its initial position, an emergency conductor leading from the last mentioned contact plate to the emergency switch, a second conductor leading from the emergency switch to the secondary pointer, a conductor leading from the signal set of the local telephone circuit to one of the emergency conductors when the switch is moved to open the circuit between the emergency conductors, and a main telephone circuit conductor connected with the broken contact ring of the secondary dial.

5. A telephone system comprising a main line, a number of telephone stations, each having a telephone instrument provided With a signal set a normally open telephone station circuit for each telephone station connected With the main line, a selecting instrument for each telephone station a selecting circuit normally Without current con. necting the selecting instruments in series whereby the. telephone station circuits of any selected two telephone stations can be closed, and an emergency circuit forming part of each telephone station circuit to be closed through the signal set of its respective telephone instrument.

6. In a telephone apparatus a telephone instrument having a telephone circuit, a signal circuit, a receiver and transmitter circuit, and an emergency circuit capable of being closed through the telephone and signal circuits, but incapable of being closed through the receiver and transmitter circuit of the telephone instrument using the emergency circuit.

7. A telephone apparatus comprising a telephone instriunent, a selecting circuit, a battery normally disconnected from the circuit and a make and break switch to rotate constantly in one direction to close the battery into the selecting circuit.

Toronto July 8th, A. D. 1907.

CHARLES FRANKLIN BRADBURN.

Signed in the presence of CHAS. H. MABER, JAMES J. BRADBURN. 

